Horsehair worm

Found in various freshwater environments such as streams, ponds, and puddles; some are also semi-aquatic.

Adults do not eat; they rely on stored nutrients. Larvae are parasites of terrestrial insects like crickets and grasshoppers.

The larvae develop inside an insect host. When mature, they manipulate the host's brain to enter water, where the adult worm emerges to mate.

They are harmless to humans, livestock, and pets. They benefit ecosystems by naturally controlling populations of crickets, grasshoppers, and beetles.